1. Field of the Invention
The present invention relates to a display device for displaying a value of a physical quantity and an extent of a change in the physical quantity, a vehicle provided with the display device, a method for displaying, a program for displaying, and a recording medium of the same.
2. Description of the Related Art
In general, a vehicle (transportation means) such as automobiles is provided with measuring sections for measuring a speed, a number of engine revolution (revolution speed), and the like, and meters such as a meter for speed (speedometer), a revolution speeder (tachometer), and the like.
Referring to reading of the meters, a driver can grasp a driving speed and the number of engine revolution (revolution speed) at a moment when the driver referred to the meters. This enables the driver to drive more appropriately.
Moreover, for example, Japanese Utility Model Publication, Jitsukaihei, 2-124559 (published on Oct. 15, 1990) discloses an acceleration display device, provided on a vehicle, so as to display acceleration measured by an acceleration sensor. The acceleration display device displays the acceleration in such a manner that an indicator extended in a radial direction from a center corresponds to an extent of the acceleration, where the center is an original point of coordinates.
A speedometer and tachometer, however, indicate a speed and revolution speed at the moment of reading: the speedometer and tachometer do not indicate extents of changes in the speed and the revolution speed. Therefore, the driver can grasp the extents of the changes, e.g., by feeling a change of scenery around a vehicle, a change in sound of engine, or other changes.
Moreover, in the art disclosed in Japanese Utility Model Publication No. 2-124559, the vehicle provided with the acceleration display device is provided with an acceleration meter (a display section for displaying the acceleration) in addition to the speedometer and tachometer.
This results in an increase in a number of the meters to be referred by the driver, thereby increasing a number of directions the driver looks to or a number of occasions the driver looks at any of the meters. This puts more burden on the driver and makes it difficult for the driver to recognize reading of each meter.